PhoneMyPc RegEdit Problems

Might be a bit of a story but here it goes,
My friend installed this software on my PC for trolling purposes and went to regedit to hide the program's files. He typed something about "systemcomponent" and setting it to 1 (or zero, forgot, sorry). He did something that hid the software's files that not even the "Show Hidden Files" folder options can reveal it. Here's the problem, I found that entry, set the "systemcomponent" back to 0 (or I think it's 1) but I stupidly deleted that rule and deleted the whole Registry key (without backups) for PhoneMyPc BEFORE uninstalling the program itself. Now I don't know if I already got rid of the software itself because he recently logged in my facebook account trolling me and clued something about "PhonyMyPc Pro". Now you might tell me I just got brute forced but my password is a combination of numbers and letters so it's a very low possibility. My questions are:

1. Did I successfully remove the PhoneMyPc program by deleting its regkey?
2. Can I get PhoneMyPc's registry key back without registry backups?
3. (If I haven't deleted the program already) How can I un-hide it so that I can uninstall it? (provided it was hidden using regedit which I only found out about because of this certain event)